Polymeric materials have enjoyed increasingly wider use in industrial and consumer products, replacing or supplementing other materials such as metals, wood and ceramiss. Chemical additives are often employed with the polymer to adapt the physical or chemical properties for particular needs. Thus, depending on requirements, it may be desirable to add one or more substances such as heat stabilizers, ultraviolet light stabilizers, antistatic agents, colorants, electrically conductive materials, flame retardant agents, smoke suppressants, foaming agents, and others. Incorporation of the additive may be accomplished by use of various methods, including dry, solution or melt blending with the polymer prior to or during thermal processing into the finished article. In some instances, the additive is merely coated onto the surface of the polymeric artccle, as in the case of certain antistatic agents which dissipate static charges or light stabilizers which absorb ultraviolet radiation.
In one prior art procedure for incorporating an ultraviolet light stabilizer into the surface of a molded polyphenylene ether resin blend, the stabilizer is dissolved in a solvent, the molded piece is immersed in the solution, and the stabilizer is absorbed into the molded surface. A disadvantage of this procedure is that the solvent aggressively attacks the polymer surface, making it tacky when wet, and thus difficult to handle until the surface is thoroughly dried.